docstr: Returns an error message if the meta-data of the supplied headers differ,
  otherwise False. 
docstr_tok: ["Returns","an","error","message","if","the","meta-data","of","the","supplied","headers","differ",",","otherwise","False","."]
code: def __diff(self, hdr1, hdr2):
      """
      Returns an error message if the meta-data of the supplied headers differ,
      otherwise False.
      """
      if not self.__same_seq(
          header.get_pixel_spacing(hdr1), header.get_pixel_spacing(hdr2)
      ):
          return "the voxel spacing is not consistent: {} != {}".format(
              header.get_pixel_spacing(hdr1),
              header.get_pixel_spacing(hdr2),
          )
      if not self.__same_seq(
          header.get_offset(hdr1), header.get_offset(hdr2)
      ):
          return "the offset is not consistent: {} != {}".format(
              header.get_offset(hdr1), header.get_offset(hdr2)
          )
          # return 'the offset is not consistent: {} != {}\n{} / {}\n{} / {}'.format(header.get_offset(hdr1), header.get_offset(hdr2), type(hdr1), type(hdr2), hdr2.NumberOfFrames if "NumberOfFrames" in hdr2 else "NONE", hdr2.ImagePositionPatient if "ImagePositionPatient" in hdr2 else 'NONE')
      else:
          return False
  
file_path: medpy/tests/io_/metadata.py
imports: import unittest
  import tempfile
  import os
  import scipy
  from medpy.io import load, save, header
  from medpy.core.logger import Logger
label_desc: Use image node_id 2 for calling the TestMetadataConsistency obj's underlying member method code with example usage: obj.__diff(hdr1, hdr2) and returns: str, str, False